The Chemistry of Cookery

found that they speedily lost flesh, and ultimately died of starvation. A multitude of similar experiments showed that gelatin alone will not support animal life, and hence the conclusion that pure gelatin is worthless as an article of food, and that ordinary soups containing gelatin owed their nutritive value to their other constituents. According to the above-named report, and the statements of Liebig, the following, which I find on a wrapper of Liebig’s ‘Extract of Meat,’ is justifiable: ‘This Extract of Meat differs essentially from the gelatinous product obtained from tendons and muscular fibre, inasmuch as it contains 80 per cent. of nutritive matter, while the other contains 4 or 5 per cent.’ Here the 4 or 5 per cent. allowed to exist in the ‘gelatinous product’ (_i.e._ ordinary kitchen stock or glaze), is attributed to the constituents it contains over and above the pure gelatin. The following, from a text-book largely used by medical students,[7] shows the estimation in which gelatin was held at that date: ‘But there is another azotised compound, Gelatin, that is furnished by animals, to which nothing analogous exists in Plants; and this is commonly reputed to possess highly nutritious properties. It may be confidently affirmed, however, as a result of experiments made upon a large scale, that Gelatin is incapable of being converted into Albumen in the animal body, so that it cannot be applied to the nutrition of the albuminous tissues. And, although it might _à priori_ be thought not unlikely that Gelatin, taken in as food, should be applied to the nutrition of the gelatinous tissues, yet neither observation nor experiment bears out such a probability.’ Further on, Dr. Carpenter says: ‘The use of gelatin as food would seem to be limited to its power of furnishing a certain amount of combustive material that may assist in maintaining the heat of the body.’ Subsequent experiments, however, have refuted these conclusions. I must not be tempted to describe them in detail, but only to state the general results, which are, that while animals fed on gelatin soup, formed into a soft paste with